


Bifurcation Theory

by callunavulgari



Category: Teen Wolf (TV)
Genre: Alternate Universe - Canon Divergence, Cunnilingus, Derek Comes Back, Derek Hale Remembers Stiles Stilinski, F/M, Lydia Martin Remembers Stiles Stilinski, M/M, Pre-Poly, Season/Series 06, Unsafe Sex, Vaginal Sex
Language: English
Status: Completed
Published: 2017-02-09
Updated: 2017-02-09
Packaged: 2018-09-23 00:37:19
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 7,208
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9631937
Author URL: https://archiveofourown.org/users/callunavulgari/pseuds/callunavulgari
Summary: Lydia sucks in another shaky breath, trying to think of a polite way to explain that she's sorry, that this was a mistake, and she didn’t mean to bother him. Just as she’s opening her mouth, Derek sighs gustily, the sound breaking apart with static in her ear.“What’s Stiles done now?” he asks, his tone resigned.She's so relieved that she gasps once, murmurs a quiet curse into the darkness of her room, and bursts into exhausted tears.





	

**Author's Note:**

> **Bifurcation theory** is the mathematical study of changes in the qualitative or topological structure of a given family, such as the integral curves of a family of vector fields, and the solutions of a family of differential equations. Most commonly applied to the mathematical study of dynamical systems, a bifurcation occurs when a small smooth change made to the parameter values (the bifurcation parameters) of a system causes a sudden 'qualitative' or topological change in its behaviour.
> 
> Basically, I went ahead and watched the sixth season of Teen Wolf and decided to make... a change. Just a small one. A change where Lydia Martin makes a phone call to Derek just after Stiles was taken. Pretty much, it was an excuse for me to write Lydia and Derek having desperate sex with each other while they're both thinking about Stiles.

Lydia’s hands are shaking, fingers wrapped so tightly around the phone that her knuckles have bled white. She should probably loosen her grip, she thinks. Money has never been an issue for her and likely never will be, but she’d gone through a phase when she was younger where she’d repeatedly broken toy after toy, just to see if her father would buy her another one. And though he had, she’d quickly learned two things. The first was a much harder lesson to learn, namely that no matter how many things that he bought for her, it wouldn’t buy her his love, or bring him back. The second was that it was senseless to break things when the replacement may not be as acceptable as the first.

She takes a deep breath and lets it out, slow and shaky, timing the breath with a careful release of pressure, fingers coming unwrapped one by one until the phone is laying unharmed against the slope of her palm. She swallows once, staring unseeingly down at the number she’s just plugged into the phone. It glows back at her steadily, waiting for her to push the call button.

With a quiet sigh, Lydia slumps forward, letting the phone fall freely onto her sheets, and rubs her aching head with one balled up fist. The ripped off post-it clenched within crinkles loudly, the corner of it scraping across her brow. She looks at it, frowning.

The handwriting is unfamiliar - all spiky bold lines, only incidentally sloppy, like whoever had written the number down had done so with haste. There’s a splotch of ink smeared across the paper, just over the first ‘e’ in Derek. She wonders at the story behind it, if the owner of the locker had fumbled in a backpack for something to write with and scrambled to get the name and number down before… what? The bell rang? Clearly he’d tossed the post-it back in his locker afterwards, but the paper was creased and worn even when she’d found it, as if whoever it belonged to had held it and worried at it with a telling frequency.

Lydia only knows of one Derek. But she’d been drawn to that locker, just like she’d been drawn to a dozen other things since this started.

She takes a deep breath, picks her phone back up, and dials.

Her hands are still trembling when a scratchy, tired voice answers a moment later.

Her eyes squeeze shut, blocking out the room beyond so she can focus on the voice. It’s groggy, thick with sleep, but it’s definitely his. Whoever had used that locker had known Derek Hale, well enough to have a way of reaching him when the rest of them didn’t.

“Derek?” Lydia whispers, her own voice wispy and quiet. Hesitant. Maybe even a little afraid.

There’s a whisper of movement over the speaker, something like fabric. She pictures him sitting up, rubbing the sleep from his eyes as he double-checked the caller ID. “Lydia?”

She breathes out a huge sigh of relief, sinking backwards until her back is pressed up against her headboard. Shakily, she draws her knees up to her chest.

She doesn’t know what to say now, Lydia realizes, staring out across her room. There’s a spread of photographs across her desk, strewn across the surface so sloppily that some of them have dropped to the floor in her haste. Most of them are candids of her and Allison, some of Jackson, even fewer of the friends that she’d had in freshmen year, the so-called queen bees that she’d put on the map, before she realized that there was more to life than being the queen of a small town high school.

Lydia had shakily set aside the pictures that seemed wrong, the ones where there were obvious gaps. Her and Scott, leaning into each other but separated by a strange empty space, big enough for another person to fit. Another, at a school dance, hers and Allison’s dresses gleaming silver, mugging at the camera as Scott stood off to the side, that same person-shaped gap separating them.

There are twelve photographs in that stack - all just barely wrong.

And all of a sudden, Lydia doesn’t know how to explain that to Derek. She isn’t accustomed to being anything other than utterly confident about her decisions, but she’s having a crisis of faith now, her breath going uneven and choppy, panic clouding her head as her heart begins to pound. She hadn’t known Derek well before, why would he believe her now when the rest of them didn’t?

Lydia sucks in another shaky breath, trying to think of a polite way to explain that she's sorry, that this was a mistake, and she didn’t mean to bother him.

Just as she’s opening her mouth, Derek sighs gustily, the sound breaking apart with static in her ear.

“What’s Stiles done now?” he asks, his tone resigned.

Lydia is so impossibly relieved that she gasps once, murmurs a quiet curse into the darkness of her room, and bursts into exhausted tears.

.

Lydia picks Derek up from the airport in Sacramento at ten am the next morning, throwing her greasy hair into a messy bun and slipping out of the house before her mother can wake up and ask her where she’s going. She spends the hour and a half that she’s behind the wheel staring out across CA-70 S, rehearsing what she’s going to say to Derek and steadily sipping on a macchiato that had gone cold far too quickly. The bagel she’d gotten along with it had gone cold even more quickly, and sits untouched on the seat next to her, hardening steadily as her stomach protested every time she’d thought to take a bite.

Derek had seemed to believe her last night, she reminds herself. He’d listened to her cry quietly for a good fifteen minutes before she’d gotten herself under control enough to admit what was wrong.

When she’d finished, he’d clicked around on a computer for awhile and told her that he’d be on the next flight out.

So, here she is. Lydia Martin, her eyes puffy with a lack of sleep, not an ounce of makeup on her, propped up against a column in the Sacramento airport, watching sleepily as Derek Hale’s plane pulls up on the tarmac.

Lydia shifts, her back scraping uncomfortably against the stone, and winces before resettling herself so that the pressure against her spine is redistributed better. There’s a woman standing off to her left, dressed neatly in a tastefully expensive suit and even more expensive heels giving Lydia the side eye.

Lydia scratches her nail idly against the webbing of her thumb, and ignores her.

Three years ago, she’d have been horrified to appear in public like this - horribly underdressed in a pair of sweats and a large t-shirt that she thinks might have once belonged to Jackson - but now, she’s finding that she really honestly doesn’t give a damn. She’d taken down armed security guards armed with nothing more than a bathrobe and her voice. She likes nice clothes, and makeup, and pretty shoes, but she doesn’t need them to feel powerful. Not anymore.

Lydia spots Derek before he spots her, which is probably a miracle in and out of itself, but elects to stay where she is - make him come to her. Besides, he’s a werewolf. A werewolf who’s just been cooped on a plane six and a half hours. He can use the exercise.

He looks softer than she remembers, his shoulders loose and, well, maybe not quite relaxed, but the closest she’s ever seen him to it. He’s skinnier too, the bulk that she remembers having given way to lean, corded muscle that’s mostly hidden beneath a soft-looking lavender sweater. Even his beard, dark and immaculately groomed, looks soft.

In fact, the only thing sharp about him are his eyes, darting from person to person. Even from here she can see his nostrils flare, searching for her scent among thousands. She grimaces, scrunching her own nose up in sympathy. Banshee or not, her nose is still perfectly ordinary, and if the smell of the airport is offensive to _her_ , she can only imagine how it is for him.

With a quiet sigh, she pushes herself upright against the column, spine straightening, and takes pity on him, quietly whistling a few bars of Peter and the Wolf until his eyes lock onto hers. She flashes him a fleeting, exhausted smile, and watches as he navigates the crowd with ease. Her lips quirk higher as a middle-aged man speaking urgently into his cell phone steps out of Derek’s way without even noticing.

“Lydia,” Derek says when he reaches her, jaw tightening incrementally. He’s carrying a small, black duffle bag in one hand, hardly big enough for a pair of shoes much less a change of outfit and toiletries, but from what she remembers of Derek, she thinks it’s probably progress that he brought anything at all.

The woman in the suit, having been distracted from her judgement of Lydia’s outfit, is now looking at Derek with admiration. The look she shoots at Lydia once she’s looked her fill is poisonous with jealousy.

“Derek,” she says, raising an eyebrow at him when all he does is stare at her. She sighs, rolling her eyes, and pushes off the pillar, leading the way to her car. Derek falls into step easily behind her.

It’s only once they’ve reached the car that Lydia sits back and really looks at Derek, her lips pursed as he takes the rock-hard bagel and tosses it into the bushes. A flock of birds descend immediately, jeering loudly at each other as they squabble for the prize.

He glances at her as he settles into the seat, his face doing something complex and unreadable. She stares at him blankly, but after a moment or so of looking, it still doesn’t resolve into something that she can read. She honestly can’t decide if he’s silently asking her something or if he just really wants her to put the car in drive.

Stiles would know, Lydia thinks vindictively, angrily switching the gearshift to drive.

Lydia swallows twice, navigating out of the airport in silence.

“Are you hungry?” she asks, when she can’t bear the quiet anymore.

She has to watch him out of the corner of her eye for a response, and sure enough, all he does is nod, watching the traffic go by outside. She supposes she should be happy for him that he’s so at peace now, but there’s a part of her that’s irrationally angry at him, the kind of hot, heavy anger that surges up from the gut and just simmers there, just behind the breastbone.

And why? Because he gets to be happy while the rest of them get to deal with the mess that his family left behind when they were all _murdered_? No. Just, no. That isn’t fair to him. If anyone deserves a happy ending, it’s Derek Hale. And this Derek, new and quiet and so at peace with himself, might even be willing to let himself have it.

.

She pulls into the first place that she sees that isn’t a McDonald's, a small vegan cafe with darkened windows and a heavy, wooden sign in exquisite penmanship.

It seems quiet, boasting a selection of food that ranges from sandwiches to sushi, the music something vaguely tasteful but largely unknown, probably a local band. The cash register is manned by a skinny hipster with hair an astonishing shade of teal, his eyes screaming boredom as he scrolls mindlessly on his phone.

When he glances up, he takes one look at Derek - eyes widening as they drop to take it all in, lovingly lingering over Derek’s biceps and waist and, of course, his crotch - before pasting a wide, flirtatious smile across his face and leaning across the counter to greet them.

For the space of a moment, Lydia regrets not squeezing herself into a pretty dress today. When the business woman had looked at her with clear judgement in her eyes, Lydia hadn’t batted an eyelash, but here, next to Derek? Lydia has never been stupid enough to think that she’s in any way unattractive, even bare-faced and dressed like a boy, but like this, next to Derek Hale, she’s… forgettable.

It’s a petty, unreasonable sort of annoyance, the kind of thing the old her would have been angry about, which just serves to annoy her even further as they step up to the counter to order.

She orders a seaweed salad, a veggie wrap, and steals a bottle of water from the cooler and goes to sit at a table by the window while Derek pays, watching with a bemused smile as he cooly navigates the conversation with a mixture of charm, politeness, and minimal flirtation. It’s more words than he’s spoken to her since she picked him up, but she can see how it costs him by the set of his shoulders as he turns away from his admirer.

“Good to see that you can still talk,” she teases, one finger absentmindedly curling around a chunk of hair that’s come loose from her bun. The tips of Derek’s ears redden as he sets a steaming mug of tea on the table and makes a face that, this time, she has no trouble deciphering.

“I can talk,” he protests with a shrug. “I just don’t like to very much.”

She smiles at him. That was something that she did already know about him, a trait that she even shares with him most days.

“Hmm,” she muses with a hum, dragging a fingernail through the condensation on her water bottle. She considers what to say, and wonders what they even have in common. They’d never known each other well and Lydia can think of only one or two times where they were ever even alone together, without the rest of the pack as a buffer, but she doesn’t ever remember being truly uncomfortable around him.

Not since he was trying to kill her anyways, but she hadn’t known about that at the time, and later, after she’d found out, it had seemed like something that she shouldn’t dwell on. He’d thought that she was a man-eating monster at the time and since then, he’d saved her at least twice.

They were even.

The food comes before she has a chance to say anything, and she tucks into it immediately, her appetite surging back with a ferocity she usually only associates with her period or sex. They chew in comfortable silence for awhile, Lydia watching out of the corner of her eye as the college-aged girl a few tables over pretends that she isn’t darting quick, admiring looks in Lydia’s direction. Her lips quirk, just a bit, as she takes a bite of her salad.

When she looks up, Derek’s watching her as he chews, the meat of his sandwich halfway to slopping out onto his plate. She raises an eyebrow in response and swallows down the bite of seaweed, daikon, and pumpkin seeds. “Yes?”

He shrugs at her, and slowly sets his sandwich back down on his plate. “No one remembers him?”

She quietly sets down her own fork, grimacing at her plate, her stomach a cold, hard knot again. “No one. Not even Scott.”

Derek winces. “But you?”

“I didn’t at first,” she tells him uncomfortably, twisting at her paper napkin until it tears. She sets it aside and tucks her hands back into her lap. “I just… something was wrong. I was having these episodes, where I would remember things, but it took a little while for me to put enough pieces together to realize that it was a person. I didn’t even know his _name_ until I called you.”

He gives her a thoughtful look, taking a sip of his tea. “None of the others feel it?”

Lydia scoffs, crossing her arms over her stomach. “They feel it, I know they do. I’ve been watching them slip all week, but none of them actually believe me.”

“Yet,” Derek says, chin lifting.

She swallows and looks away. “Yet.”

.

They roll back into Beacon Hills during the early afternoon, the late winter sun high in the cloudless sky. She hesitates just over the town line, eyes darting towards Derek. He’s been in the same position for the last hour, sprawled out with an easy grace as he flips through the book on molecular physics that he’d fished out of her backseat.

Calling Derek had been a spur of the moment decision and now that he’s here, Lydia isn’t entirely sure what she’s supposed to do with him. School won’t be out for another few hours and beyond getting him to convince the others that she’s not crazy, Lydia doesn’t really know where to start.

“Turn left,” Derek tells her without looking away from the page he’s on. She does so easily, without protest, and drives the rest of the way to his loft without any more input.

“I didn’t know you still had this,” she says as she untangles herself from her seatbelt, raising one hand to shade her eyes from the sun as she looks up at the building. It looks largely unchanged from what she remembers, though it’s strange seeing it in the daylight. Next to her, Derek tugs a keyring from his duffle, and approaches the building, using a large bronze key to unlock the front door.

“I still own it,” he explains with a shrug, stepping aside to let her pass before closing the door behind them. “Thought about renting it out a couple times, but it wasn’t worth the effort.”

She tilts her head towards the hole in the wall when they reach the top of the stairs. “Plus, you’d actually have to get around to repairing that.”

He bobs his head, fishing on the keyring for another key and sliding it home before he shoves the huge metal door back.

She takes a step inside the place, looking around. It isn’t as desolate as she’d have thought. Things are dusty, obviously - from the huge windows to the single queen-sized bed still shoved up against one wall - but none of the pipes seemed to have burst, and what’s more, no one seems to have thrown a rave here recently.

Lydia leans back against the wall and watches Derek look around the place, his nostrils flaring as his eyes burn blue. She wonders what all he’s getting - if it’s just the influx of old smells, old territory, old friends, or if there’s something that she, with her human nose, is missing.

His mouth twists with something, some private emotion, and she thinks about not asking but in the end, curiosity gets the best of her.

“What?” she asks, going for nonchalant and missing by a mile. “Getting the urge to mark your territory?”

“Stiles was here,” he says shortly, ignoring the joke with a very familiar disregard, and crossing the room to trail his fingers down a spot on the wall. “Here,” he whispers, and moves on to the kitchenette, where an ancient looking coffee machine sits alone on the empty counter, “and here,” and moves again, to the very edge of the bed, looking down at it, his face an unreadable mask as his fingers hover over the pillow, “and here.”

Lydia swallows and steps up next to him. There’s a very faint indent on the pillow, where a head might have lain.

“How many times?” she asks, heart surging against her ribcage.

 _Remember I love you_ , she hears in her head, and closes her eyes.

She’d never stopped to wonder if she was the only one that Stiles loved. If she was the only one who loved him. Judging by the hunted, aching look on Derek’s face, the careful, almost reverent way that his eyes linger over that sleepy imprint of a person, she knows that she wasn’t.

“I don’t know,” he whispers, shaking his head. “I don’t know.”

She bites her lip, letting her eyes travel the length of the room. She can almost see the tracks that Stiles made in the dust, places where it isn’t as thick, things that he must have left behind. She steps over an out of place calculus textbook as she goes to inspect the windows.

There’s a handprint there in the dust, smeared slightly around the edges, as if Stiles had dragged his fingers away too quickly. The sun is bright, dust motes heavy in the air, turning the light around her gold and bright. Tremulously, Lydia raises her own hand, holding it just over the surface of the glass, over this single, undeniable proof that Stiles was here, that he existed.

Lydia’s breath leaves her in a shaky exhale as her fingertips touch the glass, warm to the touch after a day in the sun.

When she looks away, Derek’s watching her, something soft and sad in his eyes.

“I didn’t know that you loved him,” he says, almost conversationally, if it wasn’t for the thick thread of genuine discomfort lurking on the back of his tongue. He hesitates, mouth open, as if he wants to say something more, and she wonders at that. Lydia doesn’t remember much, not nearly as much as Derek does, but she remembers who she used to be, and thinks that she probably didn’t. Not always.   
  
“I didn’t know that you did,” she whispers, and laughs, quietly, feeling a kinship that’s been absent all day. This, she thinks. This is what they had in common, other than an apparent love for tea and at least a passing interest in molecular physics.

They had Stiles in common.

“Why did you leave, if you loved him?” she asks curiously, turning away from the window and the ghost that lurks there.

Derek shrugs uncomfortably. “I thought it would go away.”

She snorts. “Clearly that isn’t working out for you.”

He glares at her for a moment. “Clearly.”

Lydia doesn’t tell him that if it didn’t go away when Stiles was _erased from existence_ , it probably never will. It would be pointless and mean, and besides, she gets the feeling that he already knows.

She watches him for another minute, going from corner to corner, hands trailing over the walls and the few objects that actually take up space in the room, as if he has to cover each and every surface with his own scent again. Or maybe he’s just mapping Stiles across the room.

Either way, it’s probably a wolf thing, she thinks, watching as he disappears down a darkly lit hallway. For lack of anything better to do, she follows him, her hands trailing and dipping along the parts of the wall that he’d touched.

When she catches up with him, he’s standing in the doorway to the bathroom. It isn’t much of one, and she gets the feeling that it used to be a meat cooler or a stock room when this building was whatever it was before Derek moved in, because there’s little more to the room than a utilitarian toilet in one corner, a beat up sink with rust clinging to the steel of the knobs and faucet, and a standing shower that doesn’t even have a cubicle. It is literally a showerhead sticking out of the wall and a drain. She stares at it for a moment, wondering if maybe it’ll resolve itself into something more human if she judges it hard enough.

There’s a bottle of Pert Plus on the ground next to it and a single bar of cheap, white soap.

She grimaces, turning her disbelieving look on Derek.

He shrugs back at her, but his ears are reddening again and he looks vaguely sheepish. “It got the job done,” he explains.

“Please tell me you have something better now.”

Derek inclines his head, taking one last look at the sad little bathroom before turning his back on it.

“I have a condo not far from Central Park,” he confesses, face twisting with some emotion that she doesn’t quite understand. Some of that must show on her face because he elaborates, looking vaguely hunted. “Laura and I bought it after the fire. It’s… up to building code.”

And probably expensive as all hell, if it’s anywhere near Central Park. She tries to picture Derek Hale living in a big city - in the _biggest_ city - dodging neighbors, getting his groceries delivered, and only leaving the house at night.

“I can’t picture you living in New York,” she muses, stepping out of his way so he can get past her. With amusement, she notes that he carefully retraces the path that she’d made with her fingers. This time, she leaves the wall alone.

“I didn’t at first,” he tells her. “Moved around a lot for awhile. But I’ve been there for a few months now and I don’t hate it.”

For Derek, not hating it is probably the highest form of praise, she thinks, perching delicately on the end of the bed and making a grab for the stress ball lying amongst the sheets. She squeezes it a couple times, testing, before she gently sets it aside.

Lydia thinks about prying some more, delicately peeling back the layers until she can see inside, but decides against it, settling back against the pillows instead. He wouldn’t appreciate her prying, she thinks. If he wanted her to know more, he’d have told her. So she stays quiet, lounging in the sun as he goes to check something on the upper floor.

She doesn’t mean to doze off, but she must because when she opens her eyes again, the sun that’s slanting through the windows is a darker shade of orange, the shadows grown long across the floor. She blinks a few times, disoriented, until she finds Derek sitting propped against the far wall, Stiles’ textbook in his lap.

She smacks her lips a few times, frowning at the gummy taste in her mouth, and sneezes twice in quick succession.

“Sorry,” she murmurs, shaking her head in an attempt to clear it. Her legs have gotten tangled in the sheets, her pant leg bunching up around her knee. It’s incredibly uncomfortable.

“You can shower if you want,” he tells her without looking away from the book. And then all of a sudden he is, his eyes sharp as his mouth twists sardonically. “If it doesn’t offend you too much, that is.”

She considers it, raising a hand to check her hair. Most of it’s come loose from her bun, hanging in unkempt curls around her face. It isn’t the worst that it’s ever been, but it’s greasy enough that she makes an audible noise of disgust when her fingers touch the roots. Derek’s lips quirk up, just barely.

“Yeah, okay,” she admits, sliding from the bed and stretching until her spine pops. “Do you have any towels?”

Derek sets the book in his lap and reaches over to root mindlessly through his duffel bag until he comes back with a plain black towel. He tosses it to her, snorting a laugh when she barely catches it. She swats him on her way past, still yawning.

“Heat’s to the right, not the left,” he calls, and she grumbles back as she steps into the horrible little bathroom, closing the door behind her. Or at least trying to - it stops short just before it closes entirely, the door not quite matching up with it’s frame.

Whatever, she thinks, and kicks off her shoes, stepping quickly out of her pants. It’s not like she expected anything else.

The water doesn’t have the decency to be fully hot, refusing to go anything above room temperature. She makes sure Derek knows just how displeased she is, muttering mutinously under her breath the entire time she's washing up. The shampoo leaves her hair a tangled mess and the soap feels like chalk going on.

To make matters worse, a drip must have started up after she turned the damn thing on, because her clothes are drenched. She scowls and honestly considers just putting the damn things right back on, wet or not. Instead, she wraps the towel around her, and goes to yell at Derek.

Derek’s taken her place on the bed while she was gone, his head settled back comfortably against the pillow, eyes closed, textbook propped open against his chest. She stops a few steps into the room, all the irritation going out of her in a rush. She huffs once and watches as his eyes slit open, tilting to the side to look at her.

He blinks twice, eyes widening almost imperceptibly as they track all the naked skin on display, dipping from the swell of her breasts straining against the towel to her wet, gooseflesh-dimpled thighs. One eyebrow goes up, slowly, and she blushes furiously, her insides going tight and hot with anticipation.

“There’s a pipe leaking,” she explains, her voice coming out breathier than she'd intended. She swallows and clenches her thighs together tightly, the heat on her face growing as Derek keeps looking at her. “My, uh. My clothes are wet.”

Derek sits up, carefully setting the book aside as he gracefully swings to his feet, loping past her and crouching in front of his duffle bag. The fabric of his jeans pulls taut across the curve of his ass, and Lydia makes a strained noise in the back of her throat.

God, she’s better than this. Derek Hale has a great ass and a great face and a great… everything, really, but he isn’t hers. Lydia wants Stiles - knows it at the core of her being, an undeniable fact that’s been chipping away at her heart for the better part of two fucking years. She loves him, because that’s fact too, and sex with Derek - sex with the man who is just as in love with Stiles as she is… it’s not just a bad idea. It’s a disaster waiting to happen.

But he’s pausing, hands hesitating in his duffle bag as his nostrils flare, and she knows what he’s smelling, and can’t do a damn thing about it.

Derek gets to his feet slowly, a loose sweater and a pair of boxers clenched in his fist and turns to face her, his eyes dark and uncertain. When he holds the clothes out to her, she takes a couple shaky steps forward, overly aware of every inch of her body.

Up close, she can see that his breathing has gone unsteady, his hands clenched so tightly around the fabric that his knuckles have bled white.

She licks her lips, peering up at him, and knows that her eyes are just as indecisive as his. Idly, she wonders how long it’s been for him. Braeden hadn’t seen him in a while, but that doesn’t necessarily mean that he’s been celibate this whole time.

Though thinking about it now, she’s guessing that’s exactly what it means.

Lydia has a choice here. She can grab the clothes, go into the next room and pretend that none of this ever happened, or she can… not.

Exhaling a slow, steady breath, she drops the towel and steps into him, her arms going around his neck as his drop to her waist. Their mouths meet, wet and open, and she shivers all over, her body crackling with electricity - the want thrilling through her.

Lydia loses a moment or two when he spins her so that her back is pressed to the wall, caught up in the heat of him, his arms trapping and caging her in as his fingers slowly map their way across her body, his mouth at her throat, his breath mixing with hers.

She doesn’t know when she closed her eyes, but they flutter open when he rubs a calloused thumb over her nipple. His eyes are sharp, calculating her response, the touch testing to see what she likes. She arches her back when he gently drags his thumbnail across it, and makes a noise low in her throat as he pinches it between two fingers, rolling it carefully between them.

“God,” she breathes, tilting her head back when those hands slide lower, across the expanse of her ribcage and over the curve of her belly, lower and lower until his fingers are sliding through her curls, testing the wetness between her legs.

Derek’s lips curve into a smile against her cheek and she closes her eyes, helplessly canting her hips up against his hand.

“Please,” she whispers as the very edge of his thumb slides into her, holding her open. There’s a finger nudging at her clit, slip-sliding through her wetness, and she says it again, pants it, her lips ghosting along the shell of his ear. She doesn’t even know what she’s asking for, her head losing that sharp clarity, going smudged around the edges, but she knows she wants it.

She can feel his smugness and doesn’t have to open her eyes to see the look on his face as he goes to his knees in front of her, taking hold of one of her calves and pulling it over his shoulder as he nuzzles his way between her legs, his breath hot against her, the tip of his nose buried in her curls.

He closes his mouth around her and sucks, hot and wet and perfect, mouthing at her folds as his tongue darts to the center of her, tasting. She sucks in a ragged gasp, her hips arching up, and whimpers when his hand clenches tight around her ankle. As he licks into her, teasing circles around her clit with the tip of his tongue and humming whenever she makes a quiet, pleased noise.

Lydia has her first orgasm like that, her fingers knotted in his hair, her thigh clenching down on his shoulder. She hovers there, just on the edge as he sucks at her clit even harder, mouth open and sloppy, until she throws her head back and comes again.

She has a feeling that if she let him, he’d keep it up, bringing her to climax after climax until her legs were weak and rubbery, until he’d no choice but to carry her over to the bed, but right now, she wants to feel him. It’s been ages since she had a dick in her hand and she wants it now, wants to undress him and see him come apart.

Gently, Lydia shoves him back, holding him back by his hair when it looks like he’s going to keep going anyways, his eyes fierce and determined, chin shiny and wet. She licks her lips, sliding her leg from his shoulder and tugging him up to her. She kisses him once, gently on the lips, and tows him over to the bed by the belt hoops.

When they reach the bed she shoves him down onto it, watching as he goes down easily. She’s sure that he lets her do it, but it makes her feel powerful anyways, watching him lay himself out against the sheets, his pupils huge and dark. He’s still dressed, the front of his jeans tented visibly, sweater mussed.

“Take off your shirt,” she whispers, and watches with genuine pleasure as his muscles bunch to do so, sliding it over his head too quickly, mussing his slightly too long hair so that it catches in his lashes. Unthinking, she steps in to straddle his hips and brushes it aside.

He makes a tiny, unthinking noise, hips hitching up against her, and her breath catches in her throat as she feels his dick slide against her. She wants that in her now, she thinks, desperately, the heat in her belly building again.

She shoves herself down his body, thumbing the tab on his pants open and sliding down his zipper with shaking fingers. She makes herself look back up at him, just to see the way that he’s watching her as she tugs his pants down around his hips, smoothly wrapping a hand around his cock. He hisses, eyes fluttering shut, hips arching upwards, and she wants to draw this out just as much as she wants this hard and fast. Wants to ride him nice and slow, until they’re both shaking and oversensitive, and then let him fuck her from behind.

Good plan, she thinks, and crawls her way back up his body, until just the thick head of his cock is nudging up against her entrance. She clenches her eyes shut, breathes out, and slides down.

Once he’s inside her she shudders once, fingers twitching as she adjusts to the stretch of him, thick and hot and heavy inside her. It’s perfect, and he’s being so good, so patient, his eyes intent on her as she clenches and unclenches around him.

She licks her lips and peers down at him. God, she thinks, dragging her fingers across the sharp line of his cheek, he really is beautiful. Gently, she cups his jaw, staring him down as his eyes lid heavily, leaning into her touch.

She rides him slow, knowing that he could flip her over at any second - that he’s letting her do this - and waits until his head is canted back, eyes closed in helpless pleasure, hands lax around her hips before she whispers, “I’ve thought about this, with him. With Stiles.”

His eyes snap open, fingers clenching tight around her hips, and for the first time, he stutters, fucking up into her once sharply before he stops himself. She smiles, slow, and rocks down again, sliding back and forth, her nails scraping over his belly.

“Did you ever fuck him?” she asks curiously, morbidly, not sure if she really wants to know.

Derek gasps as she pulls up all the way, hovering with the head of his cock barely inside her until he’s shuddering, hips twitching up towards hers. Finally he gives her a sharp nod, stilted and jerky, and she gives him what he wants, sinking down on him so quickly that it punches a gasp from them both.

“What was he like?”

Derek shivers, licks his lips twice before anything will come out. “Talkative,” he gasps, and she hitches her hips again as a reward.

She’s so stupidly wet, slick dripping between them and onto the sheets. Her voice shakes as she asks, “Did you ever fuck like this?”

Derek swallows again and nods, head bobbing up and down. “He wouldn’t shut up the entire time,” he says with a groan, hips twitching against hers again, fingers clenching down around her hips too tightly, until they’re sure to leave a bruise. “Kept going on and on about how, nngh, pretty I was.”

There’s a faint flush to the curve of his cheeks, his eyes closed more often than not, fluttering behind the lids. She wonders if he’s thinking about it, about Stiles, about fucking him, and can’t imagine that he isn’t.

“You are very pretty,” she admits, and sighs when he thrusts up into her. “Did he ever fuck you?”

“ _Yes_ ,” Derek gasps, a ragged catch to his voice. Her smile grows and then carefully, she crawls off of him, leaving him blinking at her blankly.

“Good,” she whispers, and hitches her knee invitingly. “So you can fuck me how he fucked you.”

He blinks at her and for a moment she thinks that she may have broken him, but then he’s surging into motion, pinning her to the bed, and sliding home in one smooth movement.

She gasps, head thrown back against the pillows, and wraps her legs around his waist. They hold like that, both trembling, sweat on their skin and the smell of sex heavy in the air. His lips hover over hers, so close that if either of them moved even an inch they would drag together, his breath hot against her lips. His eyes dart down to her lips before they jerk back up to her eyes.

“Does that mean I should kiss you how he kissed me?” Derek asks, his voice wrecked, and she whimpers, high and desperate.

“Yes,” she breathes, wetting her lips. “Please.”

Derek brings their lips together, a slow, sweet drag that has her toes curling against the small of his back, her hips hitching to meet his. And only then does he start to fuck her, as slowly as she’d ridden him, little hitching movements that leave her oversensitive and wanting.

“God,” she gasps as he breaks away from the kiss to suck a mark over her pulse. “Was he always this attentive?”

“Mostly,” Derek tells her absently, around a mouthful of skin. She feels his lips curve around a smile, his eyes gentling at the memory. “It was different when we first started - faster, harder, _angrier_ , but by the end-”

He cuts off, breathing hard, and thrusts sharply, head ducking to rest against her shoulder. His brow is damp with sweat, slick and cool against the heat of her skin, and she lets him have his moment.

“All right,” she whispers, drawing him in close and canting her hips, spreading her thighs a little wider. “All right. Go ahead.”

He shudders all over and this time, when he thrusts back in, he isn’t quite so careful. So reverent. His hips move between hers in a sharp steady rhythm, picking up in force and speed as they draw themselves up higher and higher, until she can barely pick out where she begins and he ends.

The rhythm falters when she comes, her legs tightening around him as she draws him in as deep as she can, pressing into the very center of her as she shakes and shakes and shakes, and then she’s only half aware of him fucking into her hard and fast, until he’s gasping a name that isn’t hers and burying his face in the damp curls clinging to the base of her neck, slamming home once, twice, three times before he buries himself there, quivering and open-mouthed.

She’ll give Derek this - he’s certainly polite, carefully easing out of her and rolling to the side before his weight becomes too much.

She breaks the silence by sneezing.

Derek snorts, turning to face her, his eyes soft and still hazy with the afterglow. He rubs a gentle hand over the curve of her hip, stroking gently. She hums quietly with pleasure, wondering if he'd ever touched Stiles like this.

“We should probably get off this bed before you catch hay fever,” Derek tells her in a scratchy, worn out voice.

“Mmm,” she agrees, and scoots closer to him, until he wraps an arm around her. “In a minute.”

“We’ll get him back, you know,” Derek whispers, just as she’s starting to drift off. Lydia squints an eye open and peers at him, considering.

“I know,” Lydia murmurs, leaning in and pressing her lips to his sternum. She closes her eyes again, more comfortable than she’s been in weeks. This, Derek with her now, feels right. This is how they get Stiles back. Her fingers link with his and squeeze, gently. “We’ll get him back together.”


End file.
